Global Sonographic Parameters

In Portosystemic Shunts In 38 Dogs & Cats

E Lindquist, D Casey, J Frank

Eric Lindquist DMV , DABVP (Canine & Feline Practice)

Director: Sound-Eklin New Jersey Mobile Associates

Founder: SonoPath.com

To Shunt Or Not To Shunt?

That Is The Question.

To ShuntNot To Shunt

PV/CVC ≥0.75 and PV/AO ≥ 0.8. D‘Anjou et. al. Vet rad and US Vol 45, No

5 2004 102 pqtients

Study Premise:

Attempt to stabilize a reliable global and precise sonographic criteria to diagnose or rule out the presence of portosystemic shunting

Study Design: Retrospective 5 Sonographers, Trained By 1 Single Evaluator Experienced in Dx Of PSS 33 Dogs & Cats with EHPSS

5 Dogs With Intrahepatic Shunts

Age Range: 2 mo- 12 yr 19/38 Sx Confirmed Bile Acids: 93-473

umol/L US Evaluation of

Bladder, Kidneys, Liver Size, PV:CVC and PV:AO Ratios

Parameter 1: The BladderNormal:

No Calculi Or Sediment

Calculi Or Sediment 24/33 (73%) EHPSS Cases. 2/5

IHPSS(40%). 68% overall.

Parameter 2: The KidneysNormal:

No Renal Calculi

Renal Calculi 32/33 (97%) Of EHPSS Cases. 3/5 for

IHPSS(60%). 92% overall

Parameter 3: Renomegaly

EHPSS 29/33. 88%IHPSS 2/5. 40%

82 % Overall

Parameter 3: Liver SizeNormal:

Subjectively Normal Liver Size

Microhepatica 33/33 EHPSS. 5/5 IHPSS.

100% Of Cases Overall

Parameters 4 & 5: Normal Portal Hilus; PV:CVC, PV:AO

RatiosNormals: PV/CVC ≥0.75 and PV/AO ≥ 0.8.

D‘Anjou et. al. Vet Rad US Vol. 45, No 5, 2004. 102 Patients

Intrahepatic Shunt Parameters

Bladder Sand/Stones: 2/5

Renal Calculi: 3/5 Renomegaly: 2/5 Microhepatica: 5/5 PV:CVC Ratio: 1:1 PV:AO Ratio: 1:1 CVC:AO Ratio: 1:1

Types Of Extrahepatic Shunts: 9 Gastrocaval (Looping), 18

Splenocaval (Short), 6 Splenoazygos (Long minimally curved)

Caval Shunts:Increased Vena Cava Volume

Gastrocaval Splenocaval

Scanning Target: Excessive Vena Caval Volume For Gastrocaval &

Splenocaval Shunts

Caval EHPSS: 9 Gastrocaval & 18 Splenocaval Shunt Ratios

(Normals PV/CVC ≥0.75 and PV/AO ≥ 0.8.)

Gastrocaval: PV/CVC: 0.4-0.67

PV/AO: 0.4-0.71

Splenocaval: PV/CVC: 0.28-0.75

PV/AO: 0.4-0.78

Azygos EHPSS Shunt Parameters

Azygos Shunt Bypasses The Cava Normal CVC:AO Ratio

6 Azygos Shunts: Normal Vena Cava Volume:

Ratios: PV/CVC:0.4-0.63 PV/AO: 0.4-0.68

PV Pre/Post Shunt Differential Double Aorta

PV/CVC Ratio 38 cases

PV/AO Ratio 38 Cases

Study Flaws

Published Controls Non blinded Urolithiasis is a non

specific finding Microhepatica &

renomegaly are subjective parameters

Caval probe pressure creates a variable

Small number of cases (38)

ConclusionsIn this population of 38 dogs

and cats, the presence of : Urinary bladder

sand/calculi, Renal mineralization Renomegaly Microhepatica

were reliable, non exclusive, positive predictive factors for the presence of PSS , but do not distinguish IHPSS from EHPSS.

Subnormal PV/CVC and PV/AO ratios (0.7 8 or less) are highly reliable indicators of the presence of EHPSS.

Any Questions?Questions?Eric.Lindquist@SonoPath.com